BOXMEER (Netherlands), January 26, 2010 – Intervet/Schering-Plough Animal Health today announces that it has received marketing authorization from the European Commission on January 12, 2010 for a single-shot vaccination schedule of its PORCILIS® PCV vaccine against porcine circovirus type 2 (PCV2) infections.

The new approval allows to vaccinate with 1 dose of 2 mL in pigs from an age of 3 weeks onwards (known as the 1 – 2 – 3 approach) in case of low to medium levels of maternal antibodies against PCV2 and also to include reduction of mortality as additional indication. This new single-shot application for PORCILIS PCV will add flexibility in use to the currently available dosage scheme of this vaccine that has been available in Europe since April 2009.

Based on the original and complementary data presented the Committee for Medicinal Products for Veterinary Use (CVMP) adopted a positive opinion after it had concluded that the quality, safety and efficacy of PORCILIS PCV for the addition of a single shot administration and the inclusion of the indication for reduction of mortality were considered to be in accordance with the requirements of Council Directive 2001/82/EC, as amended, and that the benefit-risk balance was favorable.

Major characteristics of PORCILIS PCV are that: (1) it contains the Cap-2 subunit antigen coded by ORF2 and therefore induces strong immunity against PCV2 infection; (2) it is combined with XSolve, an adjuvant offering immunity until the end of the finishing period; and (3) is able to break through of all levels of maternally-derived antibodies in piglets depending on the vaccination schedule used.

It has been demonstrated that one single dose of PORCILIS PCV induced both humoral and cell-mediated responses against PCV2, despite the presence of low to medium levels of maternal antibodies. According to a recent study published in Vaccine, the immunity induced by a single dose of the vaccine resulted in reductions of viremia, viral shedding and viral load in tissues in vaccinated pigs as compared to controls.* Moreover, field trials have demonstrated that vaccination of pigs at 3 weeks of age or older reduces the presence of virus load in the blood and reduces weight loss associated with PCV2 infection during the fattening period.

Infection with PCV2 is known to cause a variety of syndromes in pigs, together known as Porcine Circo Virus Disease (PCVD). Symptoms may include clinical signs such as weight loss or failure to grow, enlarged lymph nodes, difficulty in breathing, pale skin and jaundice.

For full prescribing information please consult the Summary of Product Characteristics.

Intervet/Schering-Plough Animal Health markets two vaccines against PCV2 infection. CIRCUMVENT PCV is produced in the USA and is intended for markets in North-, Central- and South-America, Asia (excl. Japan) and Oceania. CIRCUMVENT PCV was the first PCV2 vaccine receiving a USDA conditional license in 2005 and was launched with a full license in the USA in 2007. PORCILIS PCV is produced in Europe and is intended for the whole of Europe and Japan. PORCILIS PCV, originally developed as a two-shot vaccine, was approval Europe in 2009 and the one-shot version received European approval in January 2010. It contains Xsolve, an adjuvant that contains light liquid paraffin and dl-α-tocopheryl acetate.

About Intervet/Schering-Plough Animal Health

Intervet/Schering-Plough Animal Health, based in Boxmeer, the Netherlands, is focused on the research, development, manufacturing and marketing of animal health products. The company offers customers one of the broadest, most innovative animal Health portfolios, spanning products to support performance and to prevent, treat and control disease in all major farm and companion animal species. Intervet/Schering-Plough Animal Health is a fully owned business unit of Merck & Co., Inc., which is based in Whitehouse Station NJ, USA. For more information, visit www.intervet.com.

About Merck

Today's Merck is working to help the world be well. Through our medicines, vaccines, biologic therapies, and consumer and animal products, we work with customers and operate in more than 140 countries to deliver innovative health solutions. We also demonstrate our commitment to increasing access to health care through far-reaching programs that donate and deliver our products to the people who need them. Merck. Be Well. For more information, visit www.merck.com

This press release contains information on veterinary products based on international registration dossiers and may refer to products that are either not available in your country or are marketed under a different trade name. In addition, the approved indications as well as safety and efficacy data for a specific product may be different depending on local regulations and approvals. For more information, read the product labeling that applies to your country or contact your local Intervet/Schering-Plough Animal Health representative.